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Okay, I understand the electrical protection, Faraday cage, et al. But gravity never sleeps. And heliocopters are just a collection of parts flying in close formation, waiting for an opportunity to break formation. I think I'll pass on this past time.

Dick

Comment

I have two sons who are helicopter pilots (Apachee & A-Star) yet they are both afraid of hieghts. They tell me they are able to fly because they are in control. Jared tells me the guys that fly the power lines have to have 5,500 hrs. to get the job and have a based pay of $150,000.

Mark

"Somewhere a Village is Missing Twelve Idiots!" - Casey Anthony

I never lost a cent on the jobs I didn't get!

Comment

mark frist congrats on your kids second i belive these pilots that do this are very very good at what they do and the men that fly with them must belive so as well since there life is in there hands as well.

9/11/01, never forget.

Comment

I was actually kinda surprised, as I was under the impression that if there was no place for the electricity to flow one was safe as you were in the potential as it was, (now I realize these are super high voltage).

and no I can not say I have ever seen birds on the big transmission lines, but on the normal distribution lines that run to home transformers I see birds on from time to time,

I guess I was surprised to see the arc of electricity form the chopper to the line to bring them both to the same potential, as where is the power flowing to/from the chopper,

and if there is that much leakage to the atmosphere I would think there would be tremendous transmission line losses.

or am I jsut missing something and was not paying attention during physics class?

Push sticks/blocks Save Fingers
~~~~~~~~~~~~~~~~~~~
"The true measure of a man is how he treats someone who can do him absolutely no good."
attributed to Samuel Johnson
~~~~~~~~~~~~~~~~~~~
PUBLIC NOTICE: Due to recent budget cuts, the rising cost of electricity, gas, and oil...plus the current state of the economy............the light at the end of the tunnel, has been turned off.

Comment

there is not usually any insulation on high tension wires, there is a support core for strength and then aluminum outer wire for the current load is the normal that I have seen,
unless there is some type of transition from over head to under ground.

and If some thing was to be insulated, how much insulation would one need on the wire when the support insulators, they look to be stacks about 8 foot long, or so.

the other question I have is what could some one do crawling on the power line, even if a repair was needed, with out shutting down the line, or is it jsut an inspection of the wear points on the wire and the insulators? If I remember the narrative correctly it gave indication they could "maintain" the line with out shutting it down that way. and it looked like the point of interest was near the insulators.

Push sticks/blocks Save Fingers
~~~~~~~~~~~~~~~~~~~
"The true measure of a man is how he treats someone who can do him absolutely no good."
attributed to Samuel Johnson
~~~~~~~~~~~~~~~~~~~
PUBLIC NOTICE: Due to recent budget cuts, the rising cost of electricity, gas, and oil...plus the current state of the economy............the light at the end of the tunnel, has been turned off.

Comment

I was actually kinda surprised, as I was under the impression that if there was no place for the electricity to flow one was safe as you were in the potential as it was, (now I realize these are super high voltage).

and no I can not say I have ever seen birds on the big transmission lines, but on the normal distribution lines that run to home transformers I see birds on from time to time,

I guess I was surprised to see the arc of electricity form the chopper to the line to bring them both to the same potential, as where is the power flowing to/from the chopper,

and if there is that much leakage to the atmosphere I would think there would be tremendous transmission line losses.

or am I jsut missing something and was not paying attention during physics class?

Birds can generally land on high tension lines without a problem they do not generate the amount of potential a helicopter does helicopters generate a ton of static electricity which gives them a huge negative potential. Landing on or touching just about anything can give quit a light show. It doesn't need to be power lines to give the visual shown. A common place you will see similar effects it helicopters landing on metal ship decks. A friend in the navy told me some stories about mail drops and sailors not following the procedure of hooking the gaf hook to ground the choppers to the ship. First guy to touch the hand off gets kicked through the air from the static.

A recent accident happened in Connecticut involving High tension lines. Contractors for the power company where trimming high branches around the lines. As a safety a large grounding cable is attached to the knuckle on the bucket lift and dragged behind the truck. The man in the air is in a highly insulated fiberglass bucket to keep him safe. The ground is in case the arm comes in contact with anything it will not energizes the truck.

The arm touched one of the wires. Current went to ground. the ground turned out to be in this case a poor conductor. The ground became energized around the cable.The team safety was standing near the grounding cable and also under a line of different potential. He was killed in a way much like getting hit by lightning except it did not stop until the man became a poor conductor. I believe the lines where in the neighborhood of 25k volts.

When it comes to electricity I'll stick to the smaller stuff. 120 is a lot more predictable. 277 becomes less so but your unlikely to get nailed by it from 20feet away.

and If some thing was to be insulated, how much insulation would one need on the wire when the support insulators, they look to be stacks about 8 foot long, or so.

Yeah at those voltages I'm not sure insulation would mke much of a difference. Looking at the size of those lines it would probably also add a few tons of weight which would probably be a problem at those lengths.